Debt Instrument, Redemption Price With Change-In-Control Provision, Percentage

No definition available.

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- Definition

Line Of Credit Facility, Increase Limit

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Debt (Details) - USD ($)	1 Months Ended		12 Months Ended
Debt (Details) - USD ($)	Aug. 31, 2020	Dec. 31, 2018	Dec. 31, 2020	May 31, 2020
Bridge Facility \| Common Stock Held By Sanofi \| Bridge Loan
Debt Instrument [Line Items]
Debt, principle amount				$ 1,500,000,000
Line of credit \| Senior unsecured revolving credit facility
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 750,000,000.0
Line of credit facility, expiration period		5 years
Increase Limit		$ 250,000,000.0
Borrowings outstanding			$ 0
Line of credit \| Letters of credit
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 50,000,000.0
Senior unsecured notes
Debt Instrument [Line Items]
Interest expense			$ 17,600,000
Redemption price, percentage	100.00%
Redemption price with change-in-control provision, percentage	101.00%
Senior unsecured notes \| 2030 Notes
Debt Instrument [Line Items]
Debt, principle amount	$ 1,250,000,000
Interest rate	1.75%
Senior unsecured notes \| 2050 Notes
Debt Instrument [Line Items]
Debt, principle amount	$ 750,000,000
Interest rate	2.80%